Telescopes on the ground must observe objects in deep space through the interference of the earth's atmosphere. As light passes through the atmosphere it gets spread out by turbulence due to wind shear and changes in temperature and pressure within the atmospheric layers which effectively diminishes the resolving power of earth-based telescopes. This difficulty can be overcome to a large extent by relatively new techniques employing Laser Guide Stars (LGS) and Adaptive Optics (AO) where a bright laser illuminates a patch of sky near the target object. The laser's light is absorbed and then re-emitted by sodium atoms in the upper atmosphere, above much of the interfering lower atmosphere. The return signal can then be used to track the time-dependent atmospheric distortion of the light. Adaptive Optics uses this information to rapidly adjust optics in the telescope's instrumentation to restore the image to (nearly) what would be seen from above the atmosphere.
The University of California's Lick Observatory has been a leader in the development of adaptive optics techniques for astronomy. They are now developing an improved system using new micro-electrical mechanical systems (MEMS) technology to be installed on the Lick Observatory's three-meter Shane Telescope. This new system will very significantly improve the sharpness of the image delivered by the telescope to its instruments. Dr. Donald Gavel of the University of California-Santa Cruz is leading this effort. The new AO system is being funded by the National Science Foundation through its Major Research Instrumentation Program.
